Burglar-alarm.



G. A. BREWSTER.

BURGLAR ALARM.

APPLICATION FILED MAY29,1 912.

1,101,056. Patented June 23, 191 i b @T 'ifgmfgw y W 292W A tty FFIQ.

GEORGE A. BREWSTER, OF NEXV YORK, N. Y.

BUBGLAR-ALARM.

Specification of Letters Patent.

Patented June 23, 1914.

Application filed May 29, 1912. Serial No. 700,388.

To all whom it may concern:

Be it known that I, GEORGE AUGUSTUS Bnnwsrnn, a citizen of the United States,

and resident of the borough of Brooklyn, county of Kings, city and State of New York, have invented certain new and useful Improvements in Burglar-Alarms, of which the following is a specification.

This device is intended as a burglar alarm that can be temporarily secured to a door or window, or both, and that because of its delicate adjustment and positive operation will quickly and surely announce any attempts at unwarranted entry. The device proper, is in two distinct parts, onewhich may be secured to and is operable with the knob of a door, and the other of which may be so arranged as to secure a window at the same time giving due warning of any attempt to force an entry therethrough. A single alarm is used and suitable connections are arranged so that a movement of either device will sound the alarm, but I may arrange the parts so that separate alarms may be used for the door and window.

In the specification which follows the details of construction and the method of operation will be fully set forth.

The following is what I consider the best means of carrying out this invention.

The accompanying drawings form a part of this specification, in which: Figure 1 shows in elevation a cabinet wherein are arranged the alarm, bell and the battery, the fracture disclosing to view the location and arrangement of the battery cells. Fig. 2 shows the member intended to be used with a window. Fig. 3 shows the device intended to be used by securing or suspending from the knob bar of a door. Fig. 4 shows a clamp adapted to be'fitted to the knob. Fig. 5 shows in plan the member 14 and parts attached.

Similar reference numerals indicate like parts in all the figures where they appear.

It is my intention that the separate parts of this device as shown in Figs. 1, 2 and 3 will be electrically connected into one complete whole, and I will therefore describe them in that way commencing with the cabinet which contains the battery, or other source of electrical power, and following the course of the current.

At 1, I have indicated a cabinet, a box having a hingedly connected cover and a platform or false bottom 2 upon which I have mounted a gong 8, and a plurality of binding posts 1, 5, 6 and 7. Under the platform or false bottom 2, I place in a reclining position the cells 8 of the battery, and by means of the electrical connections and wires 9 and 10 I connect the independent cells of the battery, the bell and the binding posts in series, in such a manner that it is only necessary to close the circuit between a certain two of the binding posts to cause the bell to ring. Suspended from the bar 11 of an ordinary door catch is a circuit closer that is intended to indicate even a partial revolution of the door knob. This closer consists of a. flat bar of metal 12 of any desirable length to which I have secured the binding post 13. At the bottom of the bar 12 I have secured a slightly arched and outwardly extending member 14:, which is provided with a central longitudinal slot. Arranged one on each side of this slot and secured to the arched member 1 1 I have arranged blocks 15 of insulating material which may be fiber or hard rubber or any other suitable insulator. A screw 16, which secures in position the binding post 17 also secures the arched member 14: to the bar 12, and interposed between the bar 12 and member 14: I have inserted a piece of suitable insulating material 18, and between the binding post 17 and the bar 12 I have in serted another piece of insulating material 19, arranging these parts so that the binding post 17, and the arched member 14 will be in electrical contact with each other. but out of electrical contact with the bar 12. Near the upper end of the bar 12 I provide a lug 20 and suspended in this lug, by means of the screw 21, I have arranged a pendulum rod 22, which carries at its lowermost end a suitable weight or ball 23. This ball 23 is secured upon the rod 22 by means of a nut 24, and slidably en aged upon the rod 22 is an adjustable weight 25, secured in any desirable position by means of the knurled headed thumb screw 26.

I have before stated that the member 14. was provided with a longitudinal slot and it is through this slot that the rod 22 passes before the weight 23 is attached. The adjustable weight 25 swings above the insulating members 15 though for certain reasons which will appear later I may turn back the thumb screw 26, allowing the tapered end 27 of the weight 25 to bear upon the insulating Secured to the upper end of the bar 12 I have arranged the means by which this device is suspended from the knob bar of a door. This means consists of a clamp in two parts hingedly connected at 28, the one part 29 is secured to the bar 24 and extends upward being provided with a jaw 30. This jaw is V shaped and may be corrugated, or I may secure upon the jaw a rubber or packing member 31, an extension 32 assists in the operation of the device by providing a convenient means by which the clamp may be held while it is being secured. The opposite portion of the clamp 33 is of the same construction, size and shape as the part 29. This part 33 is not secured to the bar 12 or to any other rigid member, but is free to pivot upon the hinge 28.

Extending through the two parts of the clamp is an extended bar 34, provided with a knurled head 35 at one end, and screwthreads 36 at the other. This rod 34 passes freely through a perforation in the member 33 and is screw-threaded into the other clamping member 29. A spring 36 arranged upon the rod 34 and between the two parts 29 and 33, of the clamp forces these two parts away from each other, and a collar 37 secured upon the rod 34 determines the amount to which the clamp shall be spread. And now referring to Fig. 3 I have here shown, upon a larger scale, the window lock and contact maker. A yoke member 40 having two ends of unequal length, has one of its ends inserted into the bead of a window casing, or into a socket 41 which has been placed in the bead. Secured to the yoke is a binding post 42, and passing through the yoke and between the two sides thereof, I place a straight rod 43 inserting it into the sash 44 of the window, or into a socket 45, that has been placed therein. The rod 43 is also provided with a binding post as shown at 46. All of these parts should be of metal and I prefer that hard brass shall be used so that the parts will be of sufiicient strength to withstand the strains to which they may be subjected.

To detail the operation of my device it will be necessary to add the electrical connections, these consist of the battery leads 50 and 51 which may extend directly to one of the circuit closers. In each of these leads I have inserted a circuit tap, which consists of a plate 52 provided with a plurality of binding posts 53. There are three of these posts, one for the battery lead, and one for each of the circuits to the circuit closers.

The battery lead 50, continuing through the circuit tap 52 terminates in the binding post 13, and the battery lead 51 continuing through a similar circuit tap terminates in the binding post 17. The branching lead from the circuit 50 terminates in the binding post 46 of the window lock, and the branching lead from the circuit 51 terminates in the binding post 42. It will be seen then that a slight movement up or down of the sash 44 will bring the rod 43 in contact with one side of the yoke 40, closing the circuit and sounding the alarm, and it will also be seen that a slight movement of the knob of the door and the rod 11 to which it is attached, will cause the pendulum to swing in either direction bringing the pendulum-rod in contact with the arched member 14, thus closing the circuit. If it is found desirable to have a continuous ring alarm, the weight 25 may be allowed to slide freely upon the rod 22 and'when the pendulum carries the weight 25 off from the edge of the block 15, the weight 25 will drop securing the rod 22 in firm contact with the arched member 14.

I have found that it is sometimes desirable to secure the door circuit closing device to the knob instead of to the rod upon which the knob is mounted, and for this purpose I have provided a larger clamp as shown in Fig. 4. The operation and connections of the device and the parts not shown are in all respects similar to those shown in Fig. 2.

Modifications may be made within the scope of the appended claim without departing from the principle or sacrificing the advantages of this invention.

I-Iaving carefully and fully described my invention, what I claim and desire to secure by Letters Patent is A device of the character described comprising a horizontal metallic member having a longitudinal slot, an insulating block secured thereon and adjacent said slot, a pendulum-rod suspended above said member and passing through said slot and a weight movable longitudinally upon said rod and normally resting upon said insulating block adapted to be dislodged by a movement of the block as herein specified.

Signed at New York city, in the county of New York, and State of New York, this 21 day of May, 1912.

GEORGE A. BREWSTER. Witnesses:

G. E. STERRITIE, ARTHUR PHELPS MARR.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Iatents. Washington, D. G. 

